Electrophotographic process and apparatus for the automatic and continuous reproduction of originals



E. BLUME ET AL ELECTROPHOTOGRAPHIC PROCESS AND APPARATUS FOR THEAUTOMATIC AND CONTINUOUS REPRODUCTION OF ORIGINALS 5 Sheets-Sheet 1xEEwu R INVENTOR.S ERICH Bl UM E KURT Jns 6 ATTORN EY June 21, 1966Filed April 29, 1963 FIG.3

June 21, 1966 E. BLUME EI'AL 3,256,791

ELEGTROPHOTOGRAPHIC PROCESS AND APPARATUS FORTHE AUTOMATIC ANDCONTINUOUS REPRODUCTION OF ORIGINALS Filed April 29, 1963 5 Sheets-Sheet2 Q E k 25 -35 a N I 5 w R m 2 3* Q g m Q; Hg Q Q2: m Q Q Q k g \x I\ Qw fi- 9 i JNVENTORS ERICH B UME KURT J N S BY ATTORN Y June 21, 1966 E.BLUME ETAI. 3,256,791

ELECTROPHOTQGRAPHIC PROCESS AND APPARATUS FOR THE AUTOMATIC ANDCONTINUOUS REPRODUCTION OF ORIGINALS Filed April 29, 1965 5 Sheets-Sheet5 FIG. 4

INVENTORS E RICH a u M E KURT J NS June 21, 1966 E. BLUME ETAL 3,256,791ELEGTROPHOTOGRAPHIC PROCESS AND APPARATUS FOR THE AUTOMATIC ANDCONTINUOUS REPRODUCTION OF ORIGINALS Filed April 29. 1963 5 Sheets-Sheet4 FIG. 5

Exposure INVENTORS ERICH BLUME KURT JONS 5/3 ATTORN Y June 21, 1966 E.BLUME ETA]. 3,256,791

ELECTROPHOTOGRAPHIC PROCESS AND APPARATUS FOR THE AUTOMATIC ANDCONTINUOUS REPRODUCTION OF ORIGINALS Filed April 29, 1963 5 Sheets-Sheet5 Film San Card\ F 6 1NVENTOR.S ERICH Bl,UME KURT JONS BY 3W, 2.

ATTOR Y United States Patent 3 256,791 ELECTROPHOTOGRAlHlC PROCESS ANDAPPA- RATUS FOR THE AUTQMATIC AND CONTINU- OUS REPRQDUCTKON F URIGINALSErich Blame and Kurt .liins, Wiesbaden-Biebrich, Germany, assignors, bymesne assignments, to Azoplate Corporation, Mnrray'I-Iill, NJ.

Filed Apr. 29, 1963, Ser. No. 277,415 Claims priority, applicationGermany, Nov. 2, 1962,

9 Claims. (Cl. 95 1.7)

The present invention relates to an electrophotographic process by whichcopies preferably up to size DIN A3 (297 x 420 mm.) can be madeautomatically and continuously, with the aid of director cards,preferably from film negatives which have been inserted into a film sortcard. Further, the present invention includes an apparatus forperforming the process.

Processes and apparatuses are known, which are useful for continuousreproduction employing a web-like electrophotographic materialvwhich isexposed by contact exposure or by episcopic or diascopic projection. Inthese processes, it is, however, necessary to feed the originalsseparately into the apparatus before the reproduction process isstarted, whereupon the electrophotographic charging, exposing,developing and fixing operations automatically proceed in sequence. Inthe case that more than one copy is required from one and the sameoriginal, it is necessary to start the reproduction process for eachcopy by selection and insertion of the original by hand.

Further, it is known to stack, in a magazine, film negatives insertedinto film sort cards, and to cause a reproduction apparatus to take thesingle negatives from this magazine. In this case, however, it is alsonecessary for the number of copies to be made from a single negative tobe set by hand with a pre-selection switch.

In order to save time and effort, however, there is a great need in theart to have successive reproduction operations, in particular from filmnegatives such as are used for documentation purposes, follow each otheras rapidly as possible and completely automatically, above all'in regardto the production of plural copies. Moreover, it is important in thisautomatic operation that copies of the highest possible quality beproduced from negatives hav ing different density values. These manifoldand complicated demands are not met by the processes and apparatuseshitherto known, because they do not meet the requirements with regard toequipment, freedom from flaws, precision, and construction.

The present invention provides an electrophotographic process for theautomatic and continuous. production of reproductions, preferably ofsizes up to DIN A3, from positive or negative transparent masters. Inthis process, the transparent originals are inserted into so-called filmsort cards which may be provided with recording marks, and stacked,alternately with director cards which carry the desired reproductiondirections coded accordingly to the punched-card principle, in anintroductory section from which they consecutively and automatically arepassed to the scanning system and the optical section of the apparatuswhere the specific impulses of each director card are stored by anelectrical system and transmitted, in the optical section, to therespective film sort card, whereupon, in the optical section, theoriginal is irradiated, the image plane is swivelled by 90 and the pathof rays is further bent by 90 by means of an optical system of prisms.The optimum time of exposure is measured by a light dosage device, theimage being projected on the previously charged electrophotographicmaterial and image-wise discharging it, while the paper web issimultaneously arrested at the projection plane by an intermittentlyoperative transport mechanism, and the material is again continuouslyconveyed and subsequently developed, fixed, and cut into desired sizes.

The following is a more detailed description of the invention:

First, the transparent original must possess a suitable shape in orderto be processed in the apparatus of the present invention. In the caseof film negatives, which are preferably used in connection with thepresent invention, this is effected by inserting or cementing them intopunched cards having a window corresponding in size to thenegatives,-i.e. so-called film sort cards. FIG. 6 shows such a film sortcard to scale, which may be used in the present invention. Suitablenegatives for this special kind of film sort card are unperforated filmsof size 32 x 45 mm. or perforated films of size 24 x 36 mm. Unperforatedfilms are particularly suitable. However, the process of the presentinvention is not limited to the use of these standard film negatives,but other transparent originals preferably approximating theabove-mentioned sizes, may also be reproduced.- It is immaterialwhether. the originals are given an optimum degree of exposure or not,provided they can be reproduced at all. If the masters usedarephotoprints from originals, they may be positives or negatives. Asexplained in further detail below, it is possible in each case toproduce an image corresponding to the original, i.e. a positive,byselection of a suitable toner, viz. a positive-working toner or areversal toner.

The above mentioned film sort card, which carries the original, isplaced into a storage magazine. Below this film sort card, there isplaced the so-called director card which coacts with it. This directorcard has the same size and is provided wit-h imprints which enable it tobe marked in known maner by punching. Using a pre-determined code, thesemarks are so made that the scanning device referred to below can convertthem into corresponding impulses. This director card thus serves thepurpose of pre-determining the number of copies to be made from anoriginal.

Thus it is possible, for example, by using a director card with'twodecades, to produce up to 99 copies. If

more than 99 copies are required from one original, a director card maybe used having e.g. a division of three decades, so that up to 999copies can be'made.

In the manner stated above, the originals to be reproduced, with theirspecific director cards, are stacked one above the other in the storagemagazine. ber of cards, up to about 600, may be stacked in this manner.The cards are then removed one by one from the above-mentioned magazinewith the aid of a knifelike withdrawal device, the so-called card-knife,i.e. in each case the director card is first removed and then moved onvia a contact scanning device which scans the card for punched marks.The directions taken from the card are stored in known manner by theelectrical system, while the director cards themselves are ejected andgathered in a collecting basket, without releasing the optical,

system at this stage of operation.

The film sort card appertaining to this director card is withdrawn bythe above-mentioned card-knife and conveyed to the optical section ofthe apparatus by means of a mechanically driven roller system. In theoptical section, the movement of the card is stopped at a positionexactly beneath the irradiation device. At this stage of the operation,irradiation is effected. For this purpose, a point-shaped lightsource-preferably a high pressure mercury vapor-lar'np-is reflected viaa condenser system in the lens. Between the lens and the condensersystem, there is placed the original the image plane of which isswivelled in known manner by while the image-Wise differentiated path ofrays is deflected by 90 by means A large numarrested during exposurethereof.

of an optical system of prisms. This affords great advantages since, asshown below, it results in the production of an image which covers thewhole width of the web of electrophotographic material illuminated bythe path of rays and thus full utilization of the web in the case aformat of size DIN A4 is used, without the necessity of turning theoriginal, which in the most frequently occurring case is a film negativeof size 32 x 45 mm., such as are customarily used for documentationpurposes. The original is inserted in a film sort card with its longerside parallel to the longitudinal edge of the film sort card. If anenlargement of size DIN A3 is desired, the path of rays is deflectedonly by 90 in the optical system of 'prisms, while size and sharpness ofthe image are determined by adjustment of the lens and of the plane ofthe latent image.

To avoid heating and, thereby, damaging of the negatives, the path ofrays of the above mentioned points'haped light source is passed over aso-called cold-light mirror which transmits the infra-red rays andreflects only the rays of the visible and the ultra-violet ranges whichare desired in the illumination.

In order to obtain'the exact time of exposure, a socalled light dosagedevice is provided. This device measures the reflected or incident lightat the edges of the projected image, i.e. in the darkest areas of theimage, and thus supplies to the optical system the values indicating therange of exposure. When an optimum light quantity is attained, the lightdosage device interrupts the exposure, thus ending the illumination ofthe electrostatically charged photosemiconductor coating of theelecrophotographic material to be described in further detail below.

By a further operation, which follows automatically, the original ispassed on to a collector basket. Alternatively, if the orders on thedirector card require repetition of the reproduction operation, theabove described operation is repeated as desired, using the sameoriginal which, in this case, is not further conveyed.

There follows the next director card with the next film sort card, whichare similarly handled. The operation is repeated until the card magazineis empty. The sequence of operations is as rapid as possible and islimited only by the ability of the card and the original to withstandmechanical stress.

Prior to each exposure, the electrophotographic material differentiatedduring the preceding illumination step is further conveyed, so that theelectrostatically charged photoconductor material is always ready forexposure.

Prior to exposure, the electrophotographic material referred to above isprovided, in known manner, with an electrostatic charge from a chargingdevice. The material comprises a web-like strip. After termination ofthe exposure as described above, followed by the production of thelatent electrostatic image, the electrophotographic material isconveyed, at a constant speed, to the succeeding stations of operation,while that portion of the material which follows it in the direction offeed is This is effected by means of a loop which is successively formedand taken up.

The material bearing the latent image now passes the developing stationwhere it is contacted, in known manner, with a developer mixture appliedby a magnetic brush. Duringthis operation, a bias voltage may beapplied. The toners used may have the same polarity as the areas notstruck by light, or they may be oppositely charged. Accordingly, areversed image or an image corresponding to the charged areas will beobtained.

In the'following station, the latent image thus made visible issubjected to a heat treatment by means of an infra-red radiator in whichheat from a filament is reflected on the surface of theelectrophotographic paper from an elliptical reflector surrounding theradiator. While the thus fixed image is further conveyed, two conltrolmarks facilitate the cutting thereof into single formats. The finishedcopy drops into a basket from which it can be removed.

The present invention includes an apparatus for performing the aboveprocess, the apparatus generally comprising a card magazine forreceiving the film sort cards and the director cards, a Withdrawal andtransport device for one card at a time, a contact roll, a scanningbrush, an optical system for irradiation, provided with a coldlightmirror, a system of prisms for swivelling and defiection of the imageplane, a light dosage device, an exposure device which causes theformation of additional control marks, a projection plane which issituated in the path of rays differentiated by the original, a removableroll mounted beneath the plane and adapted to receive the web-likeelectrophotographic material, a charging device adjacent the roll, adiscontinuously driven drive roll which follows the plane in thedirection of feed, a further continuously driven roll, an oscillatingroller between the rolls which compensates the discontinuity, adeveloping device following the driven roll in the direction of feed, afixing station, a cutting device controlled by the abovementionedcontrol marks, a collector basket and, further, a light-tight housingsurrounding the entire mechanism, which also contains all the electricalequipment and the mechanical drive.

The apparatus and process for performing the present invention arefurther illustrated in the accompanying drawings in which:

FIG. 1 is a schematic view in longitudinal cross-section of theintroductory part of the apparatus.

FIG. 2 is a schematic sectional side view in elevation of the opticalsystem.

FIG. 3a is a schematic front view of the system of prisms.

FIG. 3b is another view of the system of prisms in a different position.

FIG. 4 is a longitudinal cross section of the paper feed and of theapparatus for performing the process.

FIG. 5 is a schematic view in longitudinal cross section of the drive.

FIG. 6 is a plan view of a film sort card to scale, and

FIG. 7 is a plan view of a director card.

In the card magazine 311 shown in FIG. 1, which holds a large number,viz. up to about 600, of film sort cards and director cards, thedirector cards and film sort cards are stacked above each other, thedirector card which controls the negative being placed beneath therespective film sort card. If one director card shall be applied toseveral film sort cards, all these film sort cards are arranged abovethis director card. The dimensions of the card magazine shouldpreferably be adapted to the size of the cards used, advantageously thecard sizes shown in FIGS. 6 and 7. However, it is also possible to usecards with different measurements in the apparatus.

The director card is picked up in known manner with the card knife 3 andpassed to the first pair of transport rolls 6 and 7 via a rack andpinion, over a crank gear and through the roll 4 and disc-shaped knife5. In the scanning station, which comprises the contact roll 8 and thescanning brush 9, the director card is scanned and the impulseindicating the number of copies to be made is stored in known manner bymeans of an electrical system. Subsequently, the director card isejected via the optical system, without actuating further operations.This is effected as follows: A photoelectrical resistance provided witha transmitter lamp 10 is arranged in such a manner that it is switchedon by the edge of the director card before the first row of punchestherein reaches the scanning brush 9 and the contact roll 8, and thuscloses the circuit of the scanning station. The second photoelectricresistance is not switched on until the director card has passed thepairs of rolls 12/13 and 14/ 15, the actuation of the second resistancebeing effected by means of a time delay member. Subsequently, thedirector card reaches the collecting basket 16. Then,- theabove-mentioned devices, i.e. card-knife 3, rolland disc-shaped knife 5become again operative and draw the next film sort card from the stackin the magazine. This film sort card passes on to the exposure zone andwith its edge switches off the drive motor 17, via thephotoelectricalresistance 11 and by means of magnetic coupling. The stored data,received from the director card, is released and causes the lens shutterto be opened for the desired time of exposure. This operation isrepeated for as many times as required by the stored information.Subsequently, the film sort card is also conveyed to the collectingbasket 16.

FIG. 2 shows the optical system of the apparatus. This optical systemmay be subdivided into the light optic parts and devices which serve toretransmit the incident rays.

The light optic part consists of the light source 18, e.g. a highpressure mercury vapor radiator having a very small focal spot, thecold-light mirror 19, the condenser system 20, the lens shutter 21, andthe lens 22. The cold-light mirror insures that the thermal stressexerted on the film is maintained as small as possible, since ittransmits infrared rays and reflects for the'desired illumination onlythe visible rays which are essential for the image formation.

Mirrors of this kind are described, e.g. in a publication-of the JenaerGlaswerke Schott & Gen., Mainz, Germany. A cooling blower 23 providessufiicient cooling of the lamp and the cold-light mirror. The opticalraypath proceeds from the negative 24 via the shutter and the lens tothe system of prisms, as shown in FIG. 3. This system of prisms, whichtransmits the ray path, is pivotable by 90 and mounted on the prismholder 26 by means of a pin 25. A

In the case of a projection of DIN A3 size, the ray path proceeds viathe triangular prism 27 to the projection plane 28. The negative which,when viewed from above, is readable, is thus projected as a readableimage of oblong size onto the projection plane.

In case a projection of size DIN A4 (210 x 297 mm.)

is required, a swivelling of the image by 90 will be necessary, becauseit must be reproduced at right angles to the paper web (half-sheetsize). This swivelling of the image is effected by means of a half cube29 and a surface mirror 30, the position of the negative beingunchanged.

The displacement of the lens 22 caused thereby is compensated for by ashifting of the introductory part of the apparatus. Size and sharpnessof the image are adjusted by shifting the projection plane and thelensby means of adjusted stop locations.

FIGS. 4 and 5 are schematic drawings of the paper feed, with drive, thepaper cutting device, and other technical details.

From the supply roll 32 the paper webpasses first over a chargingdevice-which, as shown in the present case, may be a plurality of coronawires 33and from there to the projection plane 28 and the transport roll34. The transport of the paper is effected as follows:

The drive motor 35 drives the sliding pin drive 37 by means of anintermediate gear 36. The chain 40 is reciprocated over a connecting rod38 attached to a sliding member 39. A sprocket wheel 41 which is movedto the right and to the left, with the reciprocating chain 40, moves thetransport roll 34 to the left only, by way of freewheeling. This causesthe paper web to move discontinuously over the projection plane 28.Since the movement of the paper web is sine-shaped due to the crankgear, no self-motivating spin of the roll 32 is caused.

Over the oscillating roll 42 the paper web is passed to the triple rolls43 which are driven overan intermediate wheel 44. From here, the paperweb passes continuously over the guide rolls 45 and 46 and the twinrolls 47 with the spooling motor flanged thereto. Between the two kindsof movementcontinuous and discontinuous-a loop is formed in the paperweb which is drawn 0E during exposure. For technical reasons, acontinuous movement of the paper web is necessary during development andinoperative.

fixation, as well as for operation of the cutting device 50.

Development may preferably be effected by means of an arrangement ofmagnetic rolls, with a revolving wheel 48 attached thereto. Particularlygood results are obtained by roll application according to copendingapplication Ser. No. 247,025, filed Dec. 26, 1962 and to Belgian PatentNo. 626,526, filed Dec. 24, 1962.

For fixation by means of the fixing device 49, a quartz burner isadvantageously used which is surrounded with a radiation reflectingsurface of such shape that the total of the infra-red radiation isconcentrated on the surface of the paper.

As a protection against re-heating, a protective shield is thrust intothe ray path when the infra-red source is During operation of theinfra-red source, this protective shield is removed from the ray path bymeans of a current-carrying electromagnet. When the current isinterrupted, the shield drops automatically into the ray path betweenthe infrared source and the electrophotographic material.

In the cutting device 50, a transport roll 51 is driven by I the triplerolls 43 through a chain drive; a pressure roll 52, which is biased by alifting magnet, effects intermittent transport of the paper during thecutting operation. Cutting of the paper is effected by a fixed lowerknife 53 in cooperation with a movable knife 54. A mark, produced bycontact exposure in the projection plane 28, is scanned by reflexgauging using a photoelectrical resistance 56 and actuates the cuttingoperation. Subsequently, the enlargement of size DIN A3 or DIN A4 isejected and drops into the collecting basket 58. An exact chronologicalsequence of these operations is repeated on additional material.

The Width of the web of electrophotographic material is such that sizesDIN A3 and DIN A4 can be reproduced, DIN A3 longitudinally of the web ofpaper and DIN A4 transversely. The roll has a fairly large capacityPaper rolls up to 300 In. or more may be used. These rolls can be easilyexchanged, i.e. the end of the preceding paper web may be attached in asimple manner to the beginning of a new paper web, so that a continuousoperation is possible and it is unnecessary to thread the new paper webin the machine.

The entire apparatus is enclosed in a light-tight housing. For betteraccessibiilty, each of the side walls is provided with a door so thatthe inner construction can be reached. The side walls referred to areprovided with openings which serve for an easy first insertion of theelectrophotographic paper. These openings are covered by light filterplates during operation of the apparatus as well as in the inoperativecondition, which permit observation of the inner operations. Thus thereproduction process cannot be disturbed when the doors are openedduring operation.

Further, such parts as the corona device, developing device, and fixingdevice, may be removed separately so that in the case of breakdowns ofthese high-duty parts, they can be quickly exchanged. Moreover, in thecase of trouble in the electrical system, the single circuit elementsmay be removed and exchanged, since they are mounted in blocks accordingto the drawer system.

The process and apparatus according to the present invention permit theautomatic and continuous reproduction of originals. In a particularlyfavorable manner, varying numbers of copies can be produced from eachoriginal used. Above all, it is of advantage that the use of acold-light mirror andthe mechanical conveying system, the negatives arehandled with care.

In addition, the process according to the present invention and theapparatus connected therewith permit a very rapid operation, because notime is lost by watching the operation and interfering with it by hand.For example, in the present case, 600 copies of size DIN A4 may be madein less than 40 minutes. Further, it is possible to process more thanone filling of the card magazine with the paper supply available in theapparatus. Optimum utilization of the web-like electrophotographicmaterial is possible by adapting the image axis to the required format.

A discontinuous operation is also possible with the apparatus accordingto the present invention. Devices such as the above-mentioned protectiveshield in front of the infra-red radiator or an interruptor switch forthe paper web prevent the electrophotographic material and the entireapparatus from being damaged by inadvertent use, in particular when theapparatus comes to a sudden halt, either voluntarily or involuntarily.Moreover, all parts which are subjected to increased stress, such as thecharging device, developing station, fixing device, cutting apparatusand electrical elements, can be easily exchanged as a whole so that, inthe case of unexpected events, these parts may be easily exchanged andoperation immediately resumed. Thus, by using the present invention forprofessional purposes, a continuous excution of incoming orders ispossible with a minimum of labor.

What is claimed is:

1. An apparatus for the automatic and continuous preparations ofreproductions comprising a card magazine for film sort cards anddirector cards, means for passing the cards to a scanning means, meansfor passing the cards to an optical system, the latter includingirradiation means, a projection plane in the path of the rays from theirradiation means, means for passing a continuous web of anelectrostatically charged electrophotographic material through theprojection plane with an intermittent motion, and means for continuouslymoving the electrophotographic material having an electrostatic imagethereon past a developing station and a fixing station, the apparatusbeing enclosed in a light-tight housing.

2. An apparatus according to claim 1 in which the optical systemincludes prism means for deflecting the rays from the irradiation means.

3. An apparatus according to claim 1 in which the optical systemincludes a light dosage means.

4. An apparatus according to claim 1 including means for cutting theelectrophotographic material.

5. A process for the automatic and continuous preparation ofreproduction which comprises withdrawing film sort cards, containingoriginals, and director cards from a storage zone, passing the cardssuccessively to a scanning zone and an irradiation zone, projecting alight image of the original on a continuous web of an electrostaticallycharged electrophotographic material moving through the irradiation zonewith an intermittent motion, and continuously moving the web having anelectrostatic image thereon past a developing station and a fixingstation.

6. A process according to claim 5 in which the rays in the irradiationzone are deflected onto the electrophotographic material.

7. A process according to claim 5 in which the time of exposure in theirradiation Zone is automatically controlled.

S. A process according to claim 5 in which the original is irradiatedwith light in the visible and ultra-violet ranges only.

9. A process according to claim 5 in which the electrophotographicmaterial is cut to a desired size after fixing the image thereon.

References Cited by the Examiner UNITED STATES PATENTS 2,297,691 10/1942Carlson -1.7 X 2,741,960 4/1956 Oldenboom 95l.7 2,791,949 5/1957 Simmonset a1 951.7 2,956,487 10/ 1960 Giaimo 951.7 3,002,434 10/ 1961 Reuter95-1.7 3,032,009 5/1962 Magnusson 95-1.7 X 3,051,568 8/1962 Kaprelian951.7 3,075,493 1/1963 Cerasani 951.7 X

EVON C. BLUNK, Primary Examiner.

1. AN APPARATUS FOR THE AUTOMATIC AND CONTINUOUS PREPARATIONS OFREPRODUCTIONS COMPRISING A CARD MAGAZINE FOR FILM SORT CARDS ANDDIRECTOR CARDS, MEANS FOR PASSING THE CARDS TO A SCANNING MEANS, MEANSFOR PASSING THE CARDS TO AN OPTICAL SYSTEM, THE LATTER INCLUDINGIRRADIATION MEANS, A PROJECTION PLANE IN THE PATH OF THE RAYS FROM THEIRRADIATION MEANS, MEANS FOR PASSING A CONTINUOUS WEB OF ANELECTROSTATICALLY CHARGED ELECTROPHOTOGRAPHIC MATERIAL THROUGH THEPROJECTION PLANE WITH AN INTERMITTENT MOTION, AND MEANS FOR CONTINUOUSLYMOVING THE ELECTROPHOTOGRAPHIC MATERIAL HAVING AN ELECTROSTATIC IMAGETHEREON PAST A DEVELOPING STATION AND A FIXING STATION, THE APPARATUSBEING ENCLOSED IN A LIGHT-TIGHT HOUSING.